Suicide rates for soldiers who served in Afghanistan increased, according to a large study. / Scott Olson, Getty Images

by Gregg Zoroya, USA TODAY

by Gregg Zoroya, USA TODAY

Suicide rates soared among soldiers who went to war in Iraq and Afghanistan and those who never left the United States, according to the largest study ever conducted on suicide in the military.

To prepare the study, researchers scanned records from nearly a million soldiers.

Scientists have long speculated that the fast-paced tempo the Army was under at home and abroad during the war years was an overall strain that contributed to suicides and that deaths were not just a factor of combat duty. The research by the National Institute of Mental Health appears to bear this out.

"A simple explanation that war is hell and you send people to war and bad things happen to those people is an incomplete explanation," says Michael Schoenbaum, an epidemiologist and lead author on the study looking at suicide rates.

The ongoing, $65 million study produced three separate research papers published online Monday by The Journal of the American Medical Association Psychiatry.

Among key findings: while suicide rates for soldiers who served in Iraq and Afghanistan more than doubled from 2004 to 2009 to more than 30-per-100,000, the trend among those who never deployed nearly tripled to between 25- and 30-per-100,000.

Rates for a civilian population of similar age and demographics remained steady at 19-per-100,000 during this time. The Army suicide rate, historically far lower than the civilian figure, surpassed it in 2008 and kept climbing.

The research tracked soldier records through the end of 2009. But suicides in the Army continued to rise thereafter, reaching a record high in 2012 before dipping last year.

Other findings revealed by the research published Monday:

â?¢ Researchers debunked theories that suicides were the result of two Army trends designed to recruit or retain people. One trend was the use of waivers for recruits with poor education or conduct records. The other was the practice of forcing soldiers to remain in the service beyond their enlistment, something known as "stop-loss." Neither practice contributed to the rise in suicides, researchers found.

â?¢ Some of the same risk factors that predict suicide - such as a history of mental health problems, a demotion in rank or a disciplinary action - also were were found to predict fatal accidents among soldiers.

â?¢ About one in four soldiers in the Army appear to suffer from at least one psychiatric disorder and one in 10 have multiple disorders.

â?¢ Women have lower suicide rates than men in the Army except during deployments.

â?¢ About a third of soldiers who attempted suicide are associated with mental disorders developed before they joined the Army, an indication that the service could do a better job of screening recruits.